Card Slip needed for return

I have returned items before at Fashion Express and never once have I needed my card slip for the return. I understand that it is to prove which and what type of card was used for payment. I have read the terms and condition and all that is says is take this tax invoice to the store where you brought it no where does it mention the payment card slip is needed too.<br> <br> I feel that if that is the case it needs to be added to your terms and conditions to prevent customer frustration.